Fluid-pressure brake.



W. V. TURNER- FLUID PRESSURE BRAKE.

APPLICATION FILED JAN-13, 1914.

1, 142,860.. Patented June 15,1915.

i WITNESSES INVENTOR WWW I'HE NORRIS PEYERS CO. PHOTO-LITHQ, WISHINGTON, D. C

WALTER v. TURNER, E EneEwoonumnnsYtvanm, AssIGNoE' TO THE WEsrI Eoi HOUSE AIR BRAKE ooMreNY, OF PENNSYLVANIA. v

ELUIn-rE ssuRE BRAKE.

Specification of Letters Patent.

' Application filed January 13, 1914. Serial No. 811,829.

To all whom it may concern:

Be it known that I, WALTER TURNER, a citizen of the UnitedStates, residing at Edgewood, in the county of Allegheny and 1 State of Pennsylvania, have invented new and useful Improvements in F luid-Pressure Brakes, of which the following is a'specification.

This invention relates to fluid pressure brakes, and more particularly to a brake controlling valve device operated upon a reduction in brake pipe pressure for supply-v 7 ing fluid to the brake cylinder.

In connection with valve devices of the above character, it is highly desirable to prevent the brakes from applying undersuch light reductions in brake pipe pressure to provide improved means .for preventingv as maybe produced bybrake pipe leakage or other causes which tend to reduce the brake pipe pressure unintentionally.

The principal object of my inventionis in service application position;

According to the drawing, my invention is shown as applied to a distributing valve device of the type employed on locomotivesfor controlling the locomotive brakes, but it will be understood that the invention may be employed in connection with the usual triple valve and various other forms of brake controlling valve devices.

As shown in the drawing, the distributing valve device comprises a casing 1 having a piston chamber 2 containing application and release piston 3, a valve chamber 4: open to brake cylinder pipe 5 and containing release slide valve 6, and valve chamber-Teonnect containing ap-.

ed to supply reservoir-8 and plication valve 9.

V V The equalizing portion of the distribut ing valve device comprises a piston 10 contained in piston chamberll open to brake pipe l2'and main slide valve 13and gradu-f' ating slide valve 14 contained in valve chamber 15 and adapted to beoperated'by piston 10. 1

16 to the usual pressure chamber 17 and plication chamber 18 is Patented June 15, 1915.

Valve chamber 15 is connected by passage j approvided Wltll a I or WILMERDING, rENNsYLv uiA, HA cortroarui'roivv V passage 19 leading to the seat of the main slide valve 13. p

According to my'improvement, an addi tional chamber 20 is provided having a pasvalve 13.

In the normal release position of the f parts, as shown in Fig. 1 of the drawing, passage 21 registers with port 22 in the main slide valve 13 and said port is connected through cavity'23 in the graduating valve 14; and port 24in the main valve 13 with exhaust passage 25. Itwill thus be seen that'the chamber 20 is normally maintained at atmospheric pressure. r Y Upon reducing-the brake pipe pressure to effect an application of the brakes,the initial 1 movementof the equalizing piston 10 shifts the graduatinguslide valve 14 to the posi-.

tion shown in Fig. 2 of the drawing. In

this position, port 22 registers with a through port 26 inthe graduating-valve, so that fluidfrom the valve chamber; 15 and the. pressure chamber. 17 p is vented to the chamber 20. 'Ifthe" reduction in brake pipe pressure is less than the reduction in p'res sure in the valve chamber 15,, due to equalization into the chamber 20, then nofurther movement of the equalizing piston toward application position will take place, and by 7 making the volume of the chamber 20, such that the equalizing pressure corresponds i with some predetermined reduction in brake pipe pressure, less than which it is desired that the brakes should not apply, it will be. i

clear that unless thereduction in brake pipe mined amount, movement of the. equalizing piston to application position will be prevented. I If, however, the reduction in brake pressure equals or exceeds this predeter pipe pressure equals or exceedsjthe predetermined amount,-then after the pressure in I the valve chamber 15 and the pressure "chamber 17 has equalized into the chamber 20, the equalizing piston 10 will be shifted.-

in the usual manner to. application position. In order to compensate forthe loss in pros sure in the'pressure chamber due to equalization into'the chamberr20, I preferably 65 sage 21 leading to the seat of the main .slide- ,vice has not been described in provide means for connecting the'reduction reservoir 20 with the application chamber upon'movement of the parts to service ap plication position.- For this purpose, an additional port or cavity 27 is provided in the main valve 13 which is adapted in service application position to connect passage 21 with a passage 28, containing a nonreturn check valve 29 and opening into passage 30 leading to the application chamber, as shown in Fig. 3 of the drawing.

By venting the pressure in the reduction reservoir 20 into the application chamber volume, the loss in pressure due to equalizing the pressure in the pressure chamber into the reduction reservoir 20 is compensated for to a large extent.

The operation of the application and release portion of the distributing valve dedetail, since the same corresponds With that of the dis tributing valve device of the well known E. T. locomotive brake apparatus.

Having now described my invention, What I claim as new and desire to secure by Letters Patent, is

1. In a fluid pressure brake, the combination with a brake pipe, of a piston subject to the opposing pressures of the brake pipe and a chamber, a main valve and a graduating valve operated by said piston for controlling the brakes, a reduction reservoir, and means operated upon the preliminary movement of the graduating valve'toward application position for venting fluid from said chamber to said reservoir.

2. In a fluid pressure brake, the combination with a brake pipe, an application chamber, and an application valve mechanism operated by the pressure in the application chamber for effecting an application of the brakes, of an equalizing valve device subject to the opposing pressures of the'brake E'opi es '01 this patent ma "be obtained. for

pipe and a valve chamber for controlling the pressure in said application chamber, a reduction reservoir, and means operated upon the initial movement of the equalizing valve device to the position for supplying fluid to the application chamber for venting fluid from said valve chamber to the reduction reservoir.

3. In a fluid pressure brake, the combination with a brake pipe, of an application chamber, means controlled by the pressure in said chamber for controlling the brakes, an equalizing valve device subject to the opposing pressures of the brake pipe and a valve chamber for controlling the pressure in the application chamber, a reduction reservoir normally at atmospheric pressure, and means operating upon the initial movement of said equalizing valve device from release position for venting fluid from said valve chamber to said reduction reservoir and for connecting the reduction reservoir with the application chamber in application positionr 4C. In a fluid pressure brake, the combination with a brake pine. an application chamber, and an equalizing valve device subject to the opposing pressures of the brake pipe and a valve chamber for controlling the pressure in the application chamber, of a reduction reservoir normally at atmospheric pressure and adapted tobe connected to said valve chamber u on the initial movement of said valve device and to the application chamber upon movement to application position.

In testimony whereof I have hereunto set my hand.

WALTER V. TURNER.

Witnesses:

A. M. CLEMENTS, B. A. OLIVER.

five cents each, by addressing the Commissioner of Patents.

Washington, 1). Q. 

